Steel Stud Walls: Breaking the Thermal Bridge

Steel stud walls are notoriously inefficient due to thermal bridging, but new construction and insulating methods are solving that problem.

Steel framing has many advantages over wood framing (see “Steel Framing:How Green?” p. 6). But it has one significant disavantage: Steel studs conduct heat extremely well. This effect is known as thermal bridging, and it can sharply reduce a wall’s effective Rvalue. The simplest and most common way to overcome this problem is to block the path of heat flow with rigid foam insulation (see Table 1). Adding rigid foam insulation not only increases the whole wall Rvalue, but it also reduces the temperature difference between the center of the cavity and the stud area. This cuts down on the possibility that black stains will form on interior walls from dirt that is attracted to cold spots on the wall surfaces.However, rigid foam insulation is an expensive solution to the problem of thermal bridging in steel stud construction. In an effort to find more cost-effective solutions, researchers here at Oak Ridge National Laboratory (ORNL) have explored many options, using both hot-box testing and computer simulations. These options have included diminishing the contact area between the studs and ...